Green Designaka Design for Environment,

Sustainable Design

Sustainable?

• Rates of use of renewable resources should not exceed their rates of regeneration;

• Rates of use of nonrenewable resources should not exceed the rate at which sustainable renewable substitutes are developed;

• Rates of pollution emission should not exceed the assimilative capacity of the environment

Deforestation

Environmental Impact

• Environmental impact=Population x GDP/person x environmental impact/unit of per capita GDP

Life Cycle Assessment (LCA)

• Describe which emissions will occur and which raw materials are used during the life of a product. This is usually referred to as the inventory step.

• Assess what the impacts of these emissions and raw material depletions are. This is referred to as the impact assessment step.

Life Cycle Assessment is multidisciplinary

• Technosphere: The modelling of technical systems, such as production processes, transport processes

• Ecosphere: The modelling of environmental mechanisms ("what happens with an emission?").

• Valuesphere: Dealing with subjective choices. This includes weighting of impact categories, selection of time horizon.

LCA for new Honda Insight(simplified: energy only)

Al Steel Rubber MPG Gasoline Total Kwh

Saved Kwh

Kg mat’l used in Honda

336 336 168

Kwh per Kg to produce

6.6 .66 3

Kwh/gal 34.8

Honda, Kwh LCA

2218 222 504 51 68200 71143 87023

Subaru Kwh LCA

0 0 0 22 158166 158166

LCA for Insight (cont.)

• Each Kwh of energy saved, prevents .65 kg of CO2 being added to the atmosphere.

• So, saving 87023 Kwh over the lifetime of the Insight means 56 metric tons less CO2 in the atmosphere

• For comparison, the world adds 30 billion tons of CO2 per year

1. Don’t design products, but life cyclesDon’t design "green" products. Instead, design environmentally sound product life cycles. Think about all material inputs and energy use of a product during its whole life cycle. From cradle to grave, or even better from cradle to cradle! One way to document your findings is the MET matrix (Materials, Energy, Toxicity). Enter some of the most important facts in a matrix:

METMaterials Energy Toxicity

Production

Use

Disposal

2. Don’t design products, but services

People do not always want a product. They want a solution for a certain problem. A service rather than a product can be the right solution. For example, a car sharing system is a solution for people that need a car occasionally. Zipcar is becoming popular in Boston, where parking space is at a premium. You can use one of the cars in your neighborhood when you need it.

3. Natural materials are not always better

It is a common belief that "natural" materials are more environmentally friendly than "artificial" or man made materials. Is this always true?

Of course, the production of 1 kg of wood causes less emissions

than the production of 1 kg of plastic. But what about the paint to preserve the wood,

the energy needed to dry, the sawing losses? In some products, you would need about ten times as much

wood as plastic. Plastics can often be recycled, wood cannot.

4. Energy consumption: often underestimated

If a product consumes energy in the use phase, it’s likely that its energy consumption has greater environmental impact than the materials used. 10 kWh electricity needs 2 kg of oil. Making 1 kg of plastic needs 1.5 to 2.5 kg of oil. A coffee machine uses 300 kWh electricity during its lifetime, equal to 60 kg of oil. For the production of the machine less than 1 kg of plastic is used

5. Increase product life time

You can influence the product life time in several ways: Make it more durable from a technical point of view,

or make it upgradeable (allowing installation of the latest chip in a computer).

More importantly, try to design the product in such a way that

people will feel attached to it. Many products are thrown away not because they are broken, but because owners got bored with them.

6. Use a minimum of material

Using less materials may seem obvious, but it can be difficult to do. Often you can reduce the amount of material by critically looking at dimensions, required strength and production techniques.

-shape (ribs, bosses, forming of sheet metal) reduce req’d thickness-substitution of materials with less environmental impact

It can even be beneficial to use materials that have a high environmental load per kilogram, if you can save weight. This is particularly true in transport, where less weight means less fuel consumption.

7. Make your product recyclable

Most products can be recycled, but relatively few are.

You can increase the chance that the product will be recycled: Products that can be disassembled easily

and have a high yield are preferred for recycling. Metals can be effectively recycled.

-Copper components reduce recyclability of steel-Recycling aluminum saves a lot of energy compared to smelting

Make sure thermoplastics can be recycled:-Do not use a lacquer or paper stickers on plastic-Do not combine different plastics.

Thermosets cannot be effectively recycled.Paper can be recycled, but fiber length decreases with each pass

8. Use recycled materials

Do not only make your product recyclable, but use recycled materials.

Don’t specify “virgin material”; specify performance instead of source.

Demand for recycled materials encourages recycling.

And there are energy economies:Aluminum from ore requires 13 kwh/kgRecycled aluminum requires .65 kwh/kg

Virgin rubber requires 10 kwh/kgRecycled rubber requires 3 kwh/kg

9. Replace toxic and hazardous materials

Aramid fibers replace asbestos in automotive brake liningsHydrofluorocarbons replace chlorofluorocarbons in air conditionersHydrofluoroalkanes replace chlorofluorocarbons in aerosol cansCitrus-oil cleaners replace toxics like CCl4Silver replaces lead in plumbing solderZinc and nickel replace cadmium plating for screws and nuts

10. Ask stupid questions!

Very often decisions are based on common practice: "We have always done it this way and it has always worked well".

Remember that Design for Environment is relatively new. Many existing products were designed without consideration

of their environmental impact.

You can make huge improvements in the environmental performance of products, with consequential cost savings, by simply asking "Why?".

LCA Software

• Most projects involve such a large number of inputs and outputs, that software has become available to keep track of it all.

• One package is SimaPro, available from Pre Consultants (www.pre.nl)

• Another is TEAM, from Ecobilan (www.ecobilan.com/uk_team.php)

• A longer list at www.howproductsimpact.net/box/home/lcasoftware.htm

You can contact sustainable design organizations

A couple of them are:

O2: an international organization. The US affiliate is at www.O2-usa.org

Centre for Sustainable Design, UK at www.cfsd.org.uk

Bibliography

• Design For Environment. T. E. Graedel and Allenby, B. R. Prentice Hall 1998.

• Cradle to Cradle: Remaking the Way We Make Things. W. McDonough and M. Braungart, 2002.

• Natural Capitalism: Creating the Next Industrial Revolution - Paul Hawken, Amory Lovins, L. Hunter Lovins